Drilling machine



Aug. 28, 1934. J, w, LEE

DRILLING MACHINE Filed May 31, 1952 6 Sheets-Sheet 1 gwumtom JOHN WLEE ww f Aug. 28, 1934. J. w. LEE 1,971,418

DRILLING MACHINE Filed May 51, 1952 s Sheet-Sheet s Aug. 28, 1934.. I J. W: LEE

DRILLING MACHINE Filed May 31, 1932 6 Sheets-Sheet 4 gwumtov JOHN WLEE sgqw 2: 11

Au'gQZS, 1934. J. w. LEE, 37L

DRILLING MACHINE Filed May 51. 1932 e Sheets Shee't '5 gmmloo .Jaaw WLEE 152- 19.,

Patented Aug. 28, 1934 1 .umreo irsmmes .YDRILLING MACHINE I John Wesley Lee, Dayton,

'Ohio, assign'or; by

. rn'esne assignments, to General Motors Cci-pora- Y 3 v tion',Detroit, Mich, a corporation of Delaware Application May 31, 1932, SeTiaINO. 614,317

14' Claims.

lThis inventionrelates to improvements in continumatic :drilling machines.

.It; is; among :the objects of the I present invention :torprovide a drilling-machine which requires 5 .thesservices of an operator for -workholder load- .ing purposes only.

Another object of the presentinventionis to provide novel workholders which cooperate with the operating "drills to "hold the workpieces in place, and which permit-the drilledworkpieces to fall ,bfi? by. gravity :as soon as the withdrawing :drills clearuthevjust d-rilledholes.

.nAIlOlihBl, obj ect f the, present invention is continuously to-move the workholders through a pre- -.determined cycle, whereby each'workholder'passes :a loading .stationg then moves through part of :said cycle where 1a rdrill' performs'its 1 operation, uthen passes an ejecting station and 'finally returnsmtowtherloading stationiagain to start an- 1 2 :other :cycle. i

1 Anotherobjectuof the present invention is to provide a mechanism for automatically. stopping the :machine intcase a drilled "workpiece becomes QStllCkzWOIkhOIdGI. Further objectscand advantages of the present inventionswill beapparent from the followingde- :scription, reference being had to the accompanying drawings :wherein ea preferred embodiment of :one form of Jthe .presentinventioni is clearly 11.539 shown. i i 1 -In the-drawings:

*Fig. 1 isa side elevation ofa drilli-ng machine embodying the presentinvention. Y FigJ' Zisa top view of the same.

Fig. 3"is-a-cross sectional viewtaken on the line-3-'3-of1 ig.1. SFig. 4-is a fragmentary sectional view looking -in-the'directionof arrow-"4 in Figfi 5.

1 Fig. 5 is-an enlarged fragmentary sectional view 1 4. taken'o'n thelinefl5 5 of-Fig. 4.

*Fig fi is an enlarged 'sectional view taken "on the :line 6-6 of'Fig. '4. A

Fig. 7 is "a fragmentary elevation looking-in the direction of arrow! in iElgJZ, them'ainTra'me of the machine being partly broken away for better disclosure of the safety stop.

Fig. -8 i is ra -sectional -view taken -on the line 8- 8 ofFig. 3. V

Fig. 9 is an enlarged fragmentary sectional view taken onthe line 99oftFig. '3.

Fig. 10 isachart illustrating progressive steps 'of a drilling operationwh'ich takes placeduring one complete circularmovementmf a workpiece.

, Referring ;to""Figs.f1 andBja/ base ZO-supports an annular i and carries V J drical form and has a'mainreinforcing rib 26 providing anannular recess 27 substantially centralof the main frame 25.:Supported on said reinforcing rib*and loc'ated-in the annular'recess --thereof'is a hollow cylindricalbracket '28 which 60 function will-be described presently. 'Al'rotary platform or'carriage -30 is slidably supported on track 3l provided by main frame 25 a bushing'32 in 'its'annular boss '33j, "which bushing is j'oui'nalled'about thecylind'rical exterior surface of the hollow bracket 28,"thus providing for'r'otation of the'carriage30 about the centerof said cylindrical member-28. Mountefld' uponthe carriage commonly of its a'xis'of rotation is a generally cripshaped "bracket "40 which slidably "supports a plurality bf drill spindie 1 supporting casings 41. As'best-"shown in Fig. '2,=six of such casingshave"beenchosen'which are guided for radial movement'on the bracket 40 in equiangular spaced relationship byV-shaped t guide members 42 which are secured to bracket fit) by screws'43. It is deemed sufficient to state that each or the drill *s'pir1'i3lltes i ivis journaled iri-b'allbearings located in'the casings 41 andthiat 'each spindle is prevei'ite'dfrom longitudinal move- I-Iient relative to' its casing; fAny suitable chuck '45 drivingly con'nects a drill d-wi'th each" drill *spindle 44.

Bracket 40 whichis1'otatab1ewith the carriage 30 comprisesa plurality (in the present instance six to correspondwith the number of drills) of arms each of which terminates into a block 51 which receives a cylindricaP-bushing'52 having its axis vertical. "A screw 52a threaded into each block -51 maintainseach bushing in position. The 90 inside diameter of the bushing 52 is just big enough to slida'bly receive a cylindrical workpiece a' can be seen in' Fig. '4. The drills 46 are adapted to cut 'a holeinto aworkpiece which akisisiat rightangles to the axis of the hole. The drillyfi as shown in-FigQ3 is performing a cutting opera- "tion and it is obvious thatthe bushing 52*an'd the dril lcocpera'te' to maintain theworkpi'ece in proper 'position without any further provisions. The slot in the bushing 52 permits chips to fall off. AMechanism'for continucusly rotating drill spindles Referrin particularlyto Figs. 2, 3, '2 and a, a motoris shown mountedonthe base '20 in any n suitable manner. A shaft 61 journaled insuitable 105 "bearings provided by reinforcing ribs 62 and 63 of the 'r'nainframe25 isdrivingly connected with the armature 'shaftfi i of motor 60 by a coupling 65; Located in the reinforcing ribs 62- and63 are taper roller eearmgs '66 an'd"-67,"respectively; for 110 rotatably supporting a shaft 68 which is parallel to shaft 61 and prevented from longitudinal movement in either direction by a collar 69 integral with shaft 68 and resting against roller bearing 67, and a washer '70, resting against the other roller bearing 66 and secured to shaft 68 by a nut '71 which is threadedly received by the end of said shaft. Shaft 68 is drivingly connected with shaft 61 by meshing gears 68a and 61a carried by the ends of shafts 68 and 61, respectively. The shaft 68 carries intermediate the reinforcing ribs 62 and 63a worm '72 which is in mesh with a worm gear '73 keyed as at '74 to a hollow spindle '75 which is supported for rotation about the axis of the cylindrical bracket 28 by taper roller bearings '76 and 7'7, located in said member. A nut '78 threadedly received by the lower end of spindle '75 maintains the worm gear I3 in engagement with a shoulder '79 of spindle '75. The end of spindle '75 which extends beyond bearings '76 carries a bevel gear which is held in position by a nut 81 threaded to the end of spindle 75. Worm gear '73 and bevel gear 80 which are both fast on spindle '75 together prevent said spindle from longitudinal movement in any direction relative to the cylindrical bracket 28. Vertically below each drill spindle casing the bracket 40 provides a recessed boss 82 which provides bearings 83 and 84 for spindles 85 and 86 respectively, to which a gear 8'7 and 88 respectively, is keyed, each one of which is also located in the recess of the boss. These two gears are in mesh with each other and gear 8'7 is in mesh with a gear 89 which is keyed to the overlying drill spindle 44 as at 90. The free end of the spindle 86 which extends beyond boss 82 has keyed thereto a bevel gear 91, which is in mesh with bevel gear 80, the thrust of the bevel gear 91 which is determined by the intermeshing angle of the bevel gears is taken up by a thrust bearing 92 which rests against the boss 82.

Mechanism for rotating the platform In the present instance the carriage 30 which carries the drill spindle casings 41 and the workholding bushings 52 is adapted to rotate so that each workpiece after having been inserted into one of the bushings 52 in a loading station A (see Fig. 2) moves through a complete circular path while the drilling operation takes place and returns to loading station A again. Pressfitted over the annular boss 33 of movable carriage 30 and concentric of the axis of rotation of the latter is a ring gear 100 which is furthermore drivingly connected with the platform by dowel-pins 101 as best shown in Fig. 3. This ring gear meshes with a smaller gear 102, keyed to a shaft 103 and retained in position thereon by a nut 104 which is threaded over the upper end of shaft 103. This shaft is rotatably supported in bearings 105 and 106 provided by a boss 107 of the main reinforcing rib 26 of main frame 25. The gear 102 rests on a thrust bearing 108 which in turn rests against boss 107. A regular Johnson clutch 109 is adapted to transmit rotary motion from the motor to the shaft 103. This clutch is well known to those skilled in the art, no detailed description or illustration of the same is therefore deemed necessary. It is sufficient to state that a worm gear 110 is loosely mounted on shaft 103 and is fast with the driver of the Johnson clutch, the driven clutch part is firmly mounted on shaft 103 and upon movement of a clutch collar 1090. from the position in Fig. 3 to that in Fig. '7 both clutch parts are in driving engagement. Worm gear 110 is in mesh with a worm 111, keyed to a shaft 112 (see also Fig. 8) which is journaled and prevented from longitudinal movement in any direction by suitable bearings (not shown) provided by the reenforcing ribs 62 and 63 of the main frame 25. Shaft 112 is drivingly connected with shaft 61 by meshing gears 112a and 61b carried by the shafts 112 and 61, respectively.

Referring more particularly to Figs. 3, 7 and 8 there is shown a hand lever 115 outside the main frame 25 which is keyed to a shaft 116, journaled in the main frame 25. Keyed to shaft 116 inside the main frame is a lever 117 which biased end 118 pivotally receives a link 119 which is also pivoted to the biased end of a lever 120, mounted on a shaft 121 which is journaled in bearings (not shown) provided by the reenforcing ribs 62 and 63 of main frame 25. Intermediate its bearings this shaft has keyed thereto as at 122 a clutch collar shifting lever 123 which is in permanent operative engagement with clutch collar 109a. When the operator rocks the hand lever 115 from the dot and dash position to the full line position in Fig. '7 the Johnson clutch 109 transmits motion from the motor to the shaft 103, and when rocking hand lever 115 in the reverse direction the clutch will be disengaged as can be readily understood.

Mechanism for moving drill spindle casings radially when platform rotates Referring particularly to Figs. 3 and 9, a disc 130 is slidably supported on an annular track 131 provided by the bracket 40 for rotation about the axis of rotation of the carriage 30. The disc 130 provides a recess 132 in which is located a cam ring 133, fastened to the disc 132 by screws 134 and located within said recess by a dowel pin 135. Recess 132 and cam ring 133 together form a cam groove 136 which receives anti-friction rollers 137 each of which is carried by a block 138, connected with a drill spindle casing 41 by a screw 139 and spaced therefrom by a collar 140, interposed between said block and the drill spindle casing. The cam groove 136 naturally has to be stationary in order to effect radial movement of the moving drill spindle casings. The periphery of the cam disc 130 is provided with gear teeth 130a which are in mesh with a plurality of equally spaced gears 141 each of which is mounted on a spindle 142 journaled in bearings 143 and 144 provided by bosses 145 of the bracket 40. To the lower end of each spindle 142 is attached a gear 146 having the same number of teeth and the same pitch diameter as the gears 141. Each one of the gears 146 meshes with a ring gear 147 which is secured centrally of the axis of rotation of the carriage 30 to bracket 28 by screws 148 and dowel pins 149. Gear 147 is of the same pitch diameter and has the same number of teeth as the gear represented by the toothed cam disc 136. As will appear from the foregoing, toothed cam disc 130, gears 141 and 146 and gear ring 14'? constitute a planetary gearing which maintains cam disc 130 stationary in spite of its support on the rotary bracket 40.

Means for definitely locating workpieces in bushings until drills operatively engage workpieces As has been expressed earlier, the bushings 52 merely slidably support a workpiece which is not sufficiently definite to locate a workpiece relative to the operating drill. As best shown in Figs. 2, 4 and 5 an arcuate track for the workpieces in the bushings is provided by a bar 150 frame as at 154 and mstsagain'st an annular.

shoulder 155 of the latter as may be seen in Fig. 3: As long as the workpieces in the bushings slide over bar 150 they aredefinitely located. and

by the time they passed the bar the drills have already operatively engaged which makes adislocation of the workpiecesimpossible. The engagement of each. drill withsan alignedworkpiece takes place in a predetermined position during. a complete revolution .of the carriage 'as8overned bythe camgroove 136.

workpiece ejecting after drilling operation The com groove 136'which determined the drill engaging position for'each workpiece during its circular movement also determines the point of disengagementof a drill from a workpiece. In Fig.2 there is shown a station E in which under oath action each drill will disengage from its workpiece whereupon the latter drops onto a chute lfiuwhich is formed by a rake-like struce ture 161 asshown in Figs 4; this structure is fastened in any suitable manner to a bracket 162 which in turn is secured totframe 153 by screws 163.. One workpiece after the other dropsonto said chute when moving past station B. The chute then guides the workpieces outside of frame 153 from where they drop mm any suitable receptaole, (not shown). v

Safety stop 7 Referring more particularly 'to Figs. 2, 4, and 7, a stop member l70is keyed to a stub shaft 171 which .is journaled in a bearing provided by a boss 172 of the frame 153. Keyed as at 173 to stub shaft 171 is a lever 174 which, by a link 175 is connected with hand lever 115; When the machine is in operation, that is, when hand lever 115 is in the full line position as shown in Fig. 7, stop member 170 is obstructing the path of a properly located workpiece in a bushing 52. The workpieces which are moving in the direction of arrow C in Fig. 2 normally drop;onto the chute 160 in position B. shouldhowever for one reason or another one of the workpieces become stuck in its bushing then the lower part of the workpiece will duringxthei movement of the bushing between station B to loading station A engage and rock stop member 170 clockwise as viewed inFig. 7, thereby moving the hand lever 115 from the full line position to the dot anddash position in Fig. 7whercby the Johnson clutch will be disengaged and rotation of the platform 30 will cease.

Chip removing means lteferring to Figs}. and-6. theframe 153 pro-, vides anannular pocket 180 into which the chips fall. The annular pocket of frame l53communi cates with a chute 181 also provided by said frame which leads into a pocket 182 provided by the mainframe25. Bracket carries apluralit'y of horizontally extending bars 183 to each of which is attached a plate 184 which fits into the annular pocket 180 andis adapted to convey; accumulated chips therein to the chute 181 fromwhere they drop into pocket 182. A chip conveyor 185 is adapted toconvey assembled chips in pocket 182' to any suitable removable receptacle (not shown). A lower sprocket wheel "186 is rotatablymounted on the biased end of a lever 187 which is pivotally mounted on the inside of the pocket 182 as at 188. A stop screw 189 extending laterally through said pocket isnormally'engaged bythc levcr 187,

thus allowing for clockwise rotation of the lever 187 only, as viewed in Fig. 1. endless con-"- veyor, including resilient metal bands .191 and rectangular fragments 192, is guided over sprocket wheel 1'86 and another sprocket wheel 193 which is.

rotatably supported adjacent the mouth .194 of the pocket 182. Rotatable in unison with sprocket wheel 193 is another sprocket wheel 195 which through a chain 196 is drivingly connected with a sprocket wheel 197, attached to a shaft 198 in any suitable manner, which shaft is journal'ed bearings provided by cylindrical bosses 199 of a'casing, 200 mounted on main reenforcing rib 26 of main frame 25 by screws 201. Mounted on shaft 198 and located within the casing 200 is a helical gear 202 which meshes with another helical gear (not shown) carried by a shaft 203 journaled in a hear ing provided by a boss 204 of main reenforcing rib 26 of main frame 25. The upper end of shaft 203 carries a gear 205 which is in constant mesh with the ring gear 100 on the carriage 30. Gear 205 rests on a thrustbearing 206 which in turn rests against boss 204. Shaft 203 is herewith held. against longitudinal movement downwardly as viewed in Fig. 3'; longitudinal movement of shaft 203 upwardly is prevented by the helical gear mounted thereon which thrust is directed downwardly as viewed in Fig. 3. It appears from the foregoing that the chain conveyor is moving in the direction of arrow 207 (see Fig. 1) as long as the carriage 30 rotates, thereby carrying accumu lated chips in the lower part of pocket 182 along the surface 208 and discharging them through mouth 194.

and water is applied to each drill.- As best shown in Fig. 3, a stationary pipe 210, connected at one end with a water pump (not shown) is connected with its other end to a flanged fitting 211 which rotatably supports a cup shaped member 212 which in turn threadedly receives a hollow plug 213. Plug 213 and member 212 are interlocked in properly adjusted position by any suitable means. A packing 214 is interposed between fitting 211 and plug 213 so as to prevent soap water from escaping between member 212 and fitting 211, respectively plug 213. A plurality of pipes 215 (inthe present instance 6 conforming with the numberof drills) communicates with the hollow chamberof plug 213 and are threaded into said plug. The other ends of the pipes215 communicate with faucets 216 which are. threaded into the bushing carrying blocks 51. Soap water is pumped from a supply (to be described) through pipe 210 intoth'e hollow chamber of plug 213 and thenthrough pipes 215 and faucets 216 from where it escapes and flushes the drills 46. The used soap water flows into pocket 182 from where it overflows through a sieve 220 into a receptacle 221 formed by the base 20 which is divided into two "separate receptacles 221 and .222 by a re enforcing rib 223. The pump which is preferably? driven by motor delivers soap water from the supply in receptacle 221 to the pipe 210; The faucets 216 may be regulated to adjust the spouting velocity of the soap water and thereby give the water spout a desired direction readily understood.

providedwhichwill be described presently. Re-

as can be ceptacle 222, provided by the base 20, contains a supply of lubricant 230. A suitable pump 231 attached to a'reenforcing rib 25a of the main bracket by screws 231a communicates with the lubricant supply through a pipe 232 carrying an oil filter 234' which dips into the lubricant supply. Pump. 231 is drivingly connected with shaft 61 by a gear 235 of the pump which meshes with gear 610.. A pipe 236 which extends through the hollow spindle and cam disc 130 has its lower end connected with the pump 231 and its upper. end with a flanged fitting 237, which rotatably supports a cup-shaped member 238, which in turn threadedly receives a hollow plug 239. Interposed between said hollow plug and the flanged fitting is a packing 246 which prevents lubricant within the hollow plug from escaping between said plug and the cup-shaped member 238, respectively, the.

flanged fitting 237. A plurality of pipes 241 (in the present instance six) communicate with the chamber within plug 239 and are threadedly received by said plug. The otherends of said pipes are connected with elbows 242 also threadedly received within ducts 243 of the bracket 40. Short pipes 244, threaded with one end into the ducts 243, terminate adjacent apertures '245 in carriage 30. Lubricant will be pumped from the supply through pipe 236, plug 239, pipes 241, ducts 243, and short pipes 244, from where the lubricant flows through apertures 245 in the carriage 30 onto the annular track 154 of the main bracket 25 thus providing for proper lubrication between said track and the sliding carriage. The lubricant leaves the track through ducts 24-5 and flows through vertically aligned ducts 247 from where it drains onto worm gear 110 which carries lubricant to the intermeshing worm 111, thus providing for proper lubrication of this worm gearing. The lubricant finally returns to the receptacle 222 only to be circulated again in the just described manner. Some of the lubricant in pipe 236 flows through a hole 250 in said pipe into ducts 251 and 252 from where the lubricant flows onto bevel gear 80, through ducts 253 in cylindrical bracket 28', past lower roller bearing 77 onto wormgear 73 from where the lubricant returns to receptacle 222.

Mode of operation I water pump and lubricant conveying pump, while the manipulation of the handlever 115 in the above described manner effects driving engagement of the Johnson clutch whereby the carriage.

30 with all the parts carried thereby commences to rotate. The operator is standing adjacent loading station A as indicated in Figs. 2 and 10 and inserts workpieces into the bushings which move between loading station A and station A1. Dur-' ing such movement of the bushings the drills are withdrawn from the interior cylindrical walls thereof but the-underlying rail 150 cooperates with the bushings to properly locate the work pieces until the drills operatively engage the same, which takes place in position A1 as governed by the shape of stationary cam groove 136. For better understanding the cooperation between one bushing and one drill during one complete circular movement of the same will be described detailedly, it being understood that such cooperation exists between any other bushing. and

drill 46 has completed the drilling operation.

Retraction of the drill. takes place when its cam roller 137 follows the descent 136a. As soon as the retracting drill clears the workpiece in position AS the same will drop through its bushing and onto chute 160 from where it falls into any suitable receptacle. The empty bushing then moves into position A again, ready to receive another workpiece which during another complete circular movement of the bushing is drilled in exactly the same manner as just described. Should for one reason or another a finished workpiece become stuck in its bushing the workpiece will engage and rock member 170 which throws the hand lever 115 from the full line position into the dot and dash position as viewed in Fig. 7, whereupon the carriage 30 ceases to rotate as explained earlier.

While the form of embodiment of the present invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

1. A machine for drilling a hole in a workpiece comprising, in combination, a rotatable carriage; a plurality of drill spindles supported by and guided for movement relative to the carriage; a plurality of workholders supported on the carriage in alignment with the drill spindles, each of said workholders being adapted to support a workpiece in'the direction of movement of the aligned drill spindle only and to prevent rotation of the same about the axis of said drill spindle and permitting its removal by gravity; means for preventing the removal by gravity of a workpiece in a workholder only until the aligned drill starts to cut into said workpiece; means for moving the drill spindles toward the workpieces in response to rotation of the carriage; and means for withdrawing the drill spindles from the workpieces after a drilling operation.

2.: A machine for drilling a hole in a workpiece comprising, in combination, a rotatable carriage; a plurality of drill spindles supported by and guided for movement relative to the carriage; a plurality of workholders supported on the carriage in alignment with the drill spindles, each of'said workholders being adapted to support a' workpiece in the direction of movement of the aligned drill spindle only and to prevent rotation of the same about the axis of said drill spindle and permitting its removal by gravity; means for preventing the removalby gravity of a workpiece in a workholder and properly locating said workpiece relative to an aligned drill only until said aligned drill starts to out into said workpiece; means for moving the drill spindles toward the workpieces in response to rotation of the carriage;

and means for withdrawing the drill spindles.

*suidedfor movement ,relativeto the carria e; a plurality ofwworkholders supported on the carriage in alignment with, the drill spindles, each of said workholders being adapted to support a work piece in the direction of movement of the aligned drill spindle only and to prevent rotation of the same about the axis of said drill spindle and pe mitting its removal by gravity; means for moving the drill spindles toward and away from the workpieces in response to rotation of the carriage; and stationary means cooperating with the moving workholdersfor holding the workpieces in the workholders in proper operating position relative to the aligned drill spindles only until the drills start to cut into'the workpieces.

4. A machine for drilling ahole in a workpiece comprising, in combination, arotatable oarriagega plurality ofdrill spindles supported on the conveyor andguided for movement relative. thereto; a D11 rality of workholders supported on, the carriage inalignment with the drill'spindles, each or said workholdersbeing adapted to support a Workpiece in .the direction of movement ,of the aligned drill spindle only and to, prevent rotation of the sameabout the axis of said drill spindle and per- .initting its: removal by gravity; means for pres venting the removal by gravity of a workpiece in a workholder onlyuntil the aligneddrills start to cut into. said workpiece; means for moving the drill spindles toward the workholders inresponse to rotationof the carriage; a stationary chute and meansior withdrawing the drills from the workpieces when the, same pass over said, chute.

5:. A machineifor drilling a hole in a. workpiece comprisingjn combination; a rotatable carriage; a plurality of drill-spindlessupported on, the carriage and guided for movement relative thereto; a plurality of workholders supported on the carriage in alignmentwiththe. drill, spindleseach of said workholders being; adapted to'support a workpiece in the direction of movement of the aligned drill spindle only and to prevent rotation of the sameabout the axis of. said drill spindle; and permitting its removal by gravity; means for preventing theremnval by gravity of a workpiece in a workholder only until the aligned drill starts to cut intosaid workpiece; a stationarywork re.- ceivingchute; means for moving: the drill spindles toward and away from the workholders in response to rotation of the carriage, said means withdrawing the drill spindles from the workpieces when the same move over said chute.

6. A machine for drilling a hole in a workpiece comprising, in combination a rotatable carriage; a plurality of drill spindles supported on the carriage and guided for movement relative thereto; a plurality of workholders supported on the carriage in alignment with the drill spindles, each of said workholders being adapted to support a workpiece in the direction of movement of the aligned drill spindle only and to prevent rotation of the same about the axis of said drill spindle and permitting its removal by gravity; means for moving the drill spindles toward and away from the workpieces in response to rotation of riage in alignment with drill spindles, each of s id workholders b in adap d to supp rt a work p e e th direction of movementot the a ig d dri l in le o ly and topr v t ota on of the same about h ax s oi. ai drill. spin le nd permi t ns i s emoval y ravity; a tationary chut means for moving the drill spindles toward and aw y f m th w kh lders in response to ro i n oi he arria e, s id mea s mo in the sp nd es w from the workpi c s wh n he sam pass over said chute; and astationary track sl-idabl upportin the workpi c s in h w holders in prope op ra ng posi on relative to t al n d dr l s; said ack terminating t such a point relative to thespindle moving means; that the work.- p c sin the w kh lde s ea e sa d track imm diately after the drills start to cut into the work.- piece l .3. A machine fordrilling a hole in a workpiece orner in combinat on a rotatable carriage; a p u a y o dr l s indles upported on t e ca riage and guided tor movement relative thereto; a plurality of workholders. supported on the carriage in alignment with the drill spindles, each of said workholders being adapted to support a workpiece in the direction of movement of the aligned drill spindle only and to prevent rotation of the same b t the x s o said dr spi dl and p rmitting, its removal by gravity; means for moving the drill spindles toward the workpieces in re sponse to rotation of the carriage; a stationary chute; meansfor withdrawing the drill spindles .from the workpieces when the same move over clutch for drivingly connecting the carriage -with the prime mover; and means operated by astuck workpiece in a workholder for shifting the vclutch into. disconnecting position. I

9. A machine for drilling a hole inter-workpiece comprising: in combination; a rotatable carriage; a, plur lity of dril pi d u p rted on the carriagetand guided for movement relation thereto; .a plurality of workholders supported on the conveyor in alignment Withthe: drill spindles ach of saidworkholdersbeing adapted tosupport a workpiece in the direction: of movement of the aligned drillspindle only andto prevent rotation of the same about theaxis of saiddriltspindleand permitting its. removal. by gravity; means for moving the drill spindles toward ;the workpieces in between the prime mover and the drill spindles;

a manually shiftable clutch for drivingly connecting the carriage with the prime mover; and means operated by a stuck workpiece in a. workholder for shifting the clutch into disengaged position. v

10. A machine for drilling a hole in a workpiece comprising, in combination, a rotatable carriage; a plurality of drill spindles supported on the carriage and guided for movement relative thereto; a plurality of workholders supported on the carriage in alignment with the drill spindles, each of said workholders being adapted to support a workpiece in the direction of movement of the aligned drill spindle only and to prevent rotation of the same about the axis of said drill spindle and permitting its removal by gravity; means for moving the drill spindles toward and away from the workholders in response to rotation of the carriage; means for preventing the removal by gravity of a workprime mover;

piece from a workholder only until the aligned drill commences to cut into said workpiece; a prime mover; a manually shiftable clutch for drivingly connecting the'carriage with the prime mover; and means operated by a stuck workpiece in a workholder for shifting the clutch into disengaged position.

11. A machine for drilling a hole in the periphery of a prismatic workpiece comprising, in combination, a rotatable carriage; a plurality of drill spindles supported on the carriage and guided for movement relative thereto; a plurality of workholders supported on the carriage in alignment with the drill spindles, each of said workholders being adapted to support a workpiece with its axis substantially vertical and permitting its removal by gravity; means for moving the drill spindles toward and away from the workholders in response to rotation of the carriage; a stationary chute being so located that after the withdrawal of the drills from the workpieces the same drop off the workholders and into said chute; a stationary track slidably supporting the lower end of the workpieces in the workholders thereby locating the workpieces in a necting position.

12. A machine for drilling a hole in'a prismatic workpiece comprising, in combination, a rotatable carriage; a plurality of drill spindles sup ported on the carriage and guided thereon for horizontal movement relative thereto; a plurality of substantially vertical bushings supported on the carriage in alignment with the drill spindles, said bushings being open at both ends for vertically slidably supporting workpieces; stationary means for moving the drill spindles relative to the carriage and the workpieces in the bushings in response to rotation of the carriage; means for withdrawing the drills from the workpieces after a drilling operation; and means for supporting the workpieces in the bushings only until the drills start to cut into said workpieces.

13. A machine for drilling a hole in a work.- piece comprising, in combination, a machine frame comprising an annular track and an annular pocket communicating through a chute with a deeper chip receiving pocket of the machine frame; a carriage rotatable on said annular, track; a plurality of drill spindles supported on the carriage and guided thereon for movement relative to the carriage; a plurality of workholders supported on the carriage in alignment with the drill spindles and vertically above the annular pocket; means for moving the drill spindles toward the workholders in response to rotation of the carriage; means'for withdrawing the drill spindles from the workholders after a drilling operation; a plate attached to the carriage and projecting into the annular pocket, said plate being adapted to move accumulated chips from said pocket to the chute; a conveyor for removing chips from the deeper pocket to the outside of the machine; and means for operating the conveyor in response to rotation of the carriage.

14. A machine for drilling av hole in a workpiece comprising, in combination, a machine frame comprising an annular track and an annular pocket communicating with a descending chute; a carriage rotatable on said annular track and including annularly and concentrically arranged gear teeth; a plurality of drill spindles supported on the carriage and guided thereon for movement relative to the carriage; a plurality of workholders supported on the car- 'riage in alignment with the drill spindles and vertically above the annular pocket; means for moving the drill spindles toward or away from the workholders in response to rotation of the carriage; a plate projecting into the annular pocket and movable therein in order to convey accumulated chips from said pocket to the chute; a movable endless conveyor adapted to convey the chips falling through said chute away from the machine, said endless conveyor including a plurality of sprocket wheels meshing with said conveyor; and means including a train of gears driven by the teeth of the carriage for driving one of said sprocket Wheels. I

JOHN WESLEY LEE. 

